Iron (trace mineral) Flashcards
Where is iron found?
Component in hemoglobin, myoglobin
What happens with bleeding?
Significant loss of iron
What is the role of transferrin?
Iron carrier in the blood to tissues throughout the body
What is ferritin and why is it important?
Iron storage proteins (important because when iron is in access, ferritin stores it for later use)
What is hepcidin?
hormone central to iron balance
reduces iron’s absorption from the intestine and release from storage
made by liver
What is hemoglobin?
oxygen-carrying protein of the red blood cells
What is myoglobin?
the oxygen-carrying protein of the muscle cells
What happens with iron overload (toxicity)?
hemochromatosis: characterized by deposits of iron containing pigment in many tissues, with tissue damage. Usually caused by a hereditary defect
Heme iron
Iron source
Based on hemoglobin & myoglobin in animal proteins
Non-heme iron
Iron source
Whole grains, legumes, dark green veg, enriched refined grains
Poorly absorbed
Enhancers to help with absorption of non-heme iron
Vitamin C (provides Fe3 - Fe2)
Organic acids (citric acid, malic acid, tartaric, lactic acid)
Meat, fish
Copper status
Iron pan cooking
Inhibitors of absorption of non-heme iron
Phytates (legumes, grains, rice) - decrease by 50%
Tannins
Calcium and phosphorus, zinc
Sources of iron
clams
beef
navy and black beans
enriched cereal
spinach
swiss chard
beef liver
What is the most common nutrient deficency?
Iron
What populations is iron important?
women in reproductive years, pregnant women, infants, toddlers, and adolescents
Iron deficiency anemia
Anemia = not enough RBCs
caused by increased need, increased loss, decreased absorption, decreased intake
Stages of iron deficiency
Stage 1: both iron stores and ferritin levels diminish. Measures of serum ferritin are most valuable in assessing iron status at this early stage; minimal to no symptoms; no overt effect on RBC formation
Stage 2: characterized by a decrease in transport iron; levels of serum iron fall, levels of iron-carrying protein transferrin increase; Total iron- binding capacity (TIBC) measures the total amount of iron that the blood can carry; start seeing symptoms: chronic fatigue, irritability, and trouble concentrating
Stage 3: iron-deficiency anemia; lack of iron limits hemoglobin production. The hemoglobin precursor, erythrocyte protoporphyrin, begins to accumulate, hemoglobin and hematocrit values decline
S&S of iron deficiency
unmotivated, apathetic, less physically fit, progresses to chronic fatigue, irritability and trouble concentrating, progresses to fatigue, weakness, headaches, apathy, pallor, poor resistance to cold temperatures
Causes of iron deficiency
Excessive blood loss
Liver dysfunction
Chronic disease
Sickle cell
Low Vit B12 or folate
Iron
